Eighteen subjects have been recruited and undergone initial evaluation (ie, chemosensory testing; chemosensory and medical history; internal medicine physical examination; otorhinolaryngological and neurological exam; blood tests). Of these, 9 have returned for repeat chemosensory testing. We will recruit approximately 60 new subjects between 12/1/95 and 11/30/96. This increase in recruitment and data collection is due to increased efficiency since the earlier phase of the study. Also, we will continue to see subjects in follow-up every 3 months. Recruitment of males will be given priority.